Actually I'd place a very large bet against the possibility that a. PASOK will top 20% and/or b. ND 30% :-) The reason that I trust Public Issue on these things is because they are a partner of the Alafouzos media group. This is a media group more pro-troika than the troika itself, often to comical extreme. I think it would be inconceivable that they would massage these numbers in any other way besides in the direction of augmenting the pro-IMF parties. Yet they consistently don't. My environment is full of PASOK 2009 voters. Among those under 70, 9 out of 10 of these people are definitely not going to vote PASOK, and among those under 40 none at all, indeed most are active supporters of one or the other left party or PASOK splinter.

I have not seen any poll that claims that either former "large"party is at 33%, and that includes the ND private opinion polls, that I have had a peek at. Indeed apart from a few outliers, most polls are broadly consistent with each other and converge on roughly the same picture.

Having said that: The one thing all pollsters seem to agree on is that this is an unprecedented political turmoil and that it is very difficult to make any predictions with great confidence.

See for example a new poll from VPRC, (again final vote estimate):

ND 22,5% (-5% from last month)
PASOK 12,5 % (+1,5% from last month)
KKE 12,5% (-1,5%)
SYRIZA 12% (-1,5%)
Anexartiti Ellines 11% (N/A)!
Dimokratiki Aristera 11,5% (-4,5%%)
LAOS 3% (-1,5%)
Chryssi Avgi 3,5% (+1%)
Greens 2,5% (-1%)
Dimokratiki Symmakhia 2% (even)

etc...

The road of excess leads to the palace of wisdom - William Blake